WO2025132739A1

WO2025132739A1 - Machine with lid detection

Info

Publication number: WO2025132739A1
Application number: PCT/EP2024/087334
Authority: WO
Inventors: Hugo BAILLY; Arnaud BIASOTTO; Baptiste CAVALLI; Bertrand GUYON; Grégoire HEITZ; laurent Seydoux
Original assignee: Societe des Produits Nestle SA; Nestle SA
Current assignee: Societe des Produits Nestle SA; Nestle SA
Priority date: 2023-12-22
Filing date: 2024-12-19
Publication date: 2025-06-26
Anticipated expiration: 2026-06-22

Abstract

A machine (10, 56) for processing a liquid food substance, such as milk or a milk-based substance, is provided. The machine (10, 56) comprises a jug (14) having a container (16), the container (16) delimiting a food cavity for containing said liquid food substance, and a lid (38) such as a removable lid (38) for covering the food cavity; a base (12) having one or more walls forming a seat for removably receiving the container (16); a lid detection system (36) configured for detecting a closed and/or an open state of the lid (38) when the container (16) is received in the seat, and a control unit (40) for controlling the machine (10, 56), wherein the control unit (40) includes a printed circuit board (42), and the lid detection system (36) comprises a sensor that is rigidly fixed to the printed circuit board (42).

Description

MACHINE WITH LID DETECTION Field of the invention The present invention relates to a machine and in particular to a machine for processing a liquid food substance such as milk or a milk-based substance. Background of the invention Beverages with processed liquid food substances such as milk or a milk-based substance are becoming increasingly popular. The best-known beverage of this type is a cappuccino type coffee. The beverage is made of an espresso topped with a portion of processed milk such as frothed milk. Processing liquid food substances, however, takes time, effort, and skill. One customary way of processing a liquid food substance is using a dedicated stirring device. Such a device usually contains a jug with a container and an impeller arranged inside the container. During turning of the impeller, the impeller drives the liquid food substance for processing the liquid food substance. Once the liquid food substance is processed to the desired degree, the liquid food substance may be poured out of the device and the beverage may be prepared. Such known devices, however, may not be ideal. For example, operating the impeller with the lid in the open state may cause spills of liquid food substance. US Patent 6,318,247 relates to an appliance for preparing hot beverages or food with stirring such as hot chocolate, for example. Other devices for stirring food products are described _{in patent documents WO 2004/043213 or DE 196 24 648. Stirring} systems with a magnetic engagement type are described in documents US 2,932,493, DE 1 131 372, US 4,537,332 and US 6,712,497. DE 89 15 094 relates to a refrigerated pot for dispensing a milk-based beverage. US Patent 3,356,349 discloses a stirring device that has a heated tank, magnetic drive means positioned under the tank for driving a hub located in the middle of the tank. Further examples of beverage processing appliances using stirring systems, in particular magnetically driven stirring systems, are disclosed in WO 2006/050900, WO 2008/142154, WO 2009/074555, WO 2010/023313, WO 2011/039222, WO 2011/039224, WO 2011/144647, WO 2016/202814, WO 2016/202815, WO 2016/202816, WO 2016/202817, WO 2017/098037, WO 2016/202818, WO 2017/216133, WO 2018/108804, WO 2018/108807, WO 2018/108808, WO 2019/101764, WO 2019/101765 and PCT/EP19/057841. It is thus an object of the present invention to propose a machine for processing liquid food substances where spills of liquid food substances can be avoided. Solution to the problem These and other objects, which become apparent upon reading the description, are solved by the subject-matter of the independent claims. Further embodiments and developments are provided in the dependent claims. According to a first aspect of the present invention, a machine for processing a liquid food substance, such as milk or a milk-based substance is proposed. The machine comprises a jug having a container, the container delimiting a food cavity for containing said liquid food substance, and a lid, such as a removable lid, for covering the food cavity. The machine further comprises a base having one or more walls such as a peripheral wall forming a seat of the base for removably receiving the container. The machine further comprises a lid detection system configured for detecting a closed and/or open state of the lid when the container is received in the seat. The machine further comprises a control unit for controlling the machine. The control unit includes a printed circuit board (PCB) and the lid detection system includes a sensor that is rigidly fixed to the printed circuit board. Within the meaning of this disclosure, the word “PCB” may be understood as any substrate or structure to which components, such as electrical or electronic components can be attached, such as mechanically and/or electrically attached. Preferably, the machine is configured for frothing milk or mixing liquid food substances. For this purpose, an impeller (such as an impeller for frothing milk) may be arranged in the jug. The impeller may be configured to be driven by a motor arranged in the base. The impeller in the jug may be magnetically driven by the motor in the base. For example, a magnetic drive with at least one first magnetic element may be provided in the base and mechanically connected to the motor, while at least one second magnetic element may be provided in or on the impeller. At least one of the first magnetic element and the second magnetic element may be a permanent magnet, whereas the other one of the first magnetic element and the second magnetic element may be a ferromagnetic element. Alternatively, both the first magnetic element and the second magnetic element may be permanent magnets. In other words, the impeller may include a magnetic follower device configured for following a magnetic driver device of the motor in the base. The jug may be devoid of a motor and/or may be removably coupled to the base and the motor provided in said base. The magnetic driver device of the motor may be magnetically coupled to the magnetic follower device of the impeller for making the impeller rotate in the jug. The machine according to the present invention is based at least partially on the idea that a closed state of the lid and an open state of the lid can be detected using a lid detection system. The lid detection system detects whether the lid is in the closed state or whether the lid is the open state. The machine may optionally inform the user about the closed or open state of the lid and/or may interrupt or stop an operation of the machine in the open state of the lid. The machine according to the present invention is further at least partially based on the idea that the lid detection system has a sensor that is rigidly fixed to the PCB of the control unit. The machine of the present invention is based at least partially on the idea that the PCB of the control unit can be used for at least partially mounting the lid detection system in a fixed manner. This saves cables for wiring, reduces the number of parts used for manufacturing the machine and reduces the size of the machine and allows easy automation of the assembly of the sensor to the printed circuit board. The machine according to the present invention is thus more compact, uses less parts and makes efficient use of the PCB that may already be present in the machine and allows automatic assembly. Preferably, the lid detection system is configured for measuring a characteristic indicative of the closed state and/or the open state of the lid, comparing the measured characteristic to an expected value thereof when the lid is in the closed or opened state, respectively, and optionally indicating the closed state or the open state of the lid to a user of the machine. The control unit may be configured to indicate the closed state or the open state of the lid to a user of the machine. Preferably, the sensor is connected, preferably electrically connected, to a component of the control unit, wherein the component is configured for analyzing a signal provided by the sensor. The component may be an integrated circuit, a processor or any other suitable component mounted on the PCB. Preferably, the sensor is at least one selected from the group including a mechanical sensor, a magnetic sensor, a capacitive sensor, a conductive sensor, an inductive sensor, an optical sensor, a sonic sensor, such as an ultrasonic sensor, or a radar sensor. The sensor may be a mechanical sensor, preferably an electrically-monitored mechanical sensor, configured for sensing the closed state and/or the open state of the lid based on a mechanical interaction of the lid with the container and/or the base. For example, the mechanical sensor may be a mechanical switch connected to a control circuit, the mechanical switch may be present in a first state when the lid is in the open state and when no mechanical interaction between the lid and the container and/or the base is present, and the mechanical switch may be in a second state when the lid is in the closed state and when the lid is in mechanical interaction with the container and/or the base. The control circuit may determine the first or second state of the switch and may determine from the first or second state of the switch whether the lid is in the open state or in the closed state. The sensor may be an optical sensor configured for sensing the closed state and/or the open state of the lid by measuring a light intensity or by using an optical beam, such as in a through-beam and/or retroreflective-beam arrangement. The optical sensor may include a light-sensitive diode, such as a photodiode, configured for measuring a light intensity. The optical sensor may further include a light emitter, such as a light emitting diode (LED). Preferably, the lid detection system and the control unit are arranged solely in or on the base, i.e. not on the jug. Preferably, the lid detection system and the control unit are arranged inside the base, such as connected to a cover plate of the base. Preferably, the base includes a peripheral wall that delimits the seat for removably receiving the container, wherein the lid detection system and preferably a sensor thereof is arranged along the peripheral wall, and/or above the container when the container is received in the seat in an operating position for processing the liquid food substance. Preferably, the peripheral wall includes a cut-out and/or window and the lid detection system, or the sensor thereof, detects light received through the cut-out and/or window. In other words, the lid detection system or a sensor thereof may be arranged at a position that faces the cut-out and/or window, and/or senses light transmitted through the cut-out and/or window. Preferably, the lid detection system or the sensor thereof is arranged at a retracted position recessed within the base with respect to the cut-out and/or window, preferably such that the lid detection system or the sensor thereof does not extend into and/or through the cut-out and/or window. In other words, the lid detection system may be arranged at a position that is further away in a radial direction from a central longitudinal axis of the seat than the peripheral wall. Preferably, the control unit is configured for receiving a signal such provided by the lid detection system, wherein the signal is indicative of the closed state and/or the open state of the lid. Preferably, the control unit is configured for comparing the received signal with expected values for the closed state and/or the open state of the lid, respectively, and is optionally configured for transmitting a notification to a user of the machine indicating the closed state or the open state of the lid. Preferably, the signal is indicative of a light intensity measured when the lid is closed and/or a light intensity measured when the lid is open. The signal may, alternatively or additionally, be indicative of a runtime difference between a transmitted beam directed to the lid and a received beam reflected from the lid. The runtime difference may be used, for example, in a time-of-flight (TOF) application to determine the open or closed state of the lid. Preferably, the container includes a rim delimiting a top opening of the food cavity, the lid is arranged on the container for closing the top opening, the lid includes a side wall, and the side wall is arranged in front of the sensor when the lid is in the closed state. In other words, the lid may block or at least partially block the sensor when the lid is in the closed state. In such a configuration, the lid may reduce a light intensity received by the sensor and/or may reduce a runtime difference between a transmitted beam directed to the lid and a received beam reflected from the lid. The reduction in light intensity and/or runtime difference may be used to determine whether the lid is in the closed or open state. In yet other words, a portion of the lid, e.g. its side wall, may overlap the sensor (e.g., by overlapping the cut-out and/or the window), e.g. in a direction along the central longitudinal axis of the seat. Preferably, the control unit is configured for disabling a processing of the liquid food substance when a signal provided by the lid detection system indicates the open state of the lid. For example, the control unit may disable or stop a motor of the machine such that the impeller does no longer turn inside the container, when the open state of the lid is detected. Preferably, the base of the machine is configured for receiving multiple jugs, such as in a side-by-side configuration, wherein each jug includes a container with a lid, such as a removable lid, wherein each container is received in a corresponding seat of the base and wherein the lid detection system is configured for detecting the open sate and/or the closed state of a respective lid for each jug individually. Preferably, the lid detection system includes multiple sensors, and each sensor is configured for sensing the open state and/or the closed state of the respective lid. In other words, a sensor for each jug may be provided. Preferably, the multiple sensors are arranged in a side-by- side configuration. For example, the sensors are arranged such that a line-of-sight axis of a first sensor and a line-of-sight axis of a second sensor confine an internal (interior) angle, wherein the internal angle may be in a range between about 20° and about 170°. Preferably, the multiple sensors are arranged to face away from each other. Further embodiments and aspects of the present invention are explained using the accompanying schematic figures, which are incorporated herein and constitute a part of the specification. These figures are merely exemplary. They are not to be understood as limiting the scope of the present disclosure. Brief description of the drawings _{- Figure 1 is a schematic view of a machine according to the} present invention. _{- Figure 2 is schematic view of a jug insertable into a base of} the machine of Fig. 1. _{- Figure 3 is another schematic view of the machine of Fig. 1.} _{- Figure 4 is schematic top view of the machine of Fig. 1.} _{- Figure 5 is a schematic detailed view of the machine of Fig.} 1. _{- Figure 6 is a schematic view of another machine according to} the present invention. Detailed description Within the figures, same components are referenced by the same reference numerals. Figure 1 shows a schematic view of a machine 10 for processing a liquid food substance such as milk or a milk-based substance. The machine 10 may be used to provide frothed milk such as frothed milk for a cappuccino type beverage. The machine 10 may also be used to provide hot chocolate or may be used for processing any other (hot or cold) liquid food substance. The machine 10 includes a base 12. In the specific embodiment shown, the base 12 is configured for receiving two jugs 14 in a side- by-side configuration. In other embodiments not shown, the base 12 may be configured for receiving a different number of jugs 14 such as one jug 14 or more than two jugs 14. The jugs 14 are removably received in a respective seat of the base 12. Each jug 14 includes a container 16 delimiting a food cavity for containing the liquid food substance. An impeller 17 is arranged inside the container 16 for processing the liquid food substance. The machine 10 includes a motor with a magnetic drive magnetically coupled to the impeller 17 for driving the same. More details on the motor and the magnetic coupling are _{given in, for example, in WO 2006 050 900 A1 incorporated herein} by reference in its entirety which is why no further details are provided here. The base 12 of the machine 10 includes a bottom face 18 configured for placing the machine 10 on an external support surface such as a countertop. The base 12 further includes a top face 20 opposite the bottom face 18. The top face 20 may be formed by a cover plate of the machine 10. The base 12 further includes at least one peripheral side face 22. The peripheral side face 22 may also be called peripheral lateral face. The peripheral side face 22 extends between the bottom face 18 and the top face 20. The peripheral side face 22 includes a front portion 24 and a rear portion 26 opposite the front portion 24. The front portion 24 is configured for facing a user of the machine 10 when processing the liquid food substance. The rear portion 26 is configured for facing away from the user when processing the liquid food substance. The front portion 24 may be a portion of the peripheral side face 22 where a handle 28 of the jug 14 protrudes from the peripheral side face 22. In other words, the front portion 24 may be a portion of the peripheral side face 22 where a user of the machine 10 may grab the handle 28 such as for removing and/or inserting the jug 14. The base 12 further includes one or more walls, such as a peripheral wall 30 forming the seat of the base 12 so that the container 16 of the jug 14 can be inserted into or removed from the base 12. The peripheral wall 30 may be a curved wall such as an arcuate or circular wall. The peripheral wall 30 may be adapted to the shape of the container 16 for forming the seat of the container 16. As can be further seen in Figure 1, a user interface 32 is provided along the top face 20 of the base 12. The user interface 32 allows a user of the machine 10 to interact with machine 10 and vice versa. The user interface 32 includes one or more man- machine-interface sections (MMI-sections) 34 such as buttons, levers or indicators for interaction between the user and the machine 10. The MMI-sections 34 are configured for performing a function such as initiating preparation of a cold beverage, initiating preparation of a hot beverage, displaying information to the user regarding a progress of a requested processing of the liquid food substance, displaying information to the user regarding a temperature of the liquid food substance, displaying information to the user regarding a parameter of the machine 10 that requires a user intervention, displaying locally stored and/or remotely emitted graphic or text matter, a notepad function, and a visual ambiance generator. For example, the MMI-sections 34 may be used to activate or deactivate a heater for the jug 14, and/or may be used to activate or deactivate a drive for driving the impeller 17 of the jug 14, and/or may be used to perform any other suitable user-machine-interaction. As can be further seen in Figure 1, the machine 10 further includes a lid detection system 36. The lid detection system 36 is configured for detecting a closed state and/or an open state of a lid when the container 16 is received in the seat of the base 12. The lid detection system 36 may be configured for measuring a characteristic indicative of the presence or absence of the lid, comparing the measured characteristic to an expected value thereof when the lid is present or absent, and optionally indicating the presence or absence of the lid to a user of the machine. The lid detection system 36 may include a sensor. The sensor may be a mechanical sensor, a magnetic sensor, a capacitive sensor, a conductive sensor, an inductive sensor, an optical sensor, a sonic sensor, such as an ultrasonic sensor, or a radar sensor, or any other type of sensor suitable to determine the closed and/or open state of the lid. For example, the sensor may be a mechanical sensor such as an electrically-monitored mechanical sensor, and the sensor may be configured for sensing the closed and/or open state of the lid based on a mechanical interaction of the lid with the container 16 and/or the base 12. Additionally or alternatively, the sensor may be an optical sensor configured for sensing the closed and/or open state of the lid by measuring a light intensity received by the sensor, or by using an optical beam arrangement. The lid detection system 36 is explained in more detail with reference to Figures 4 and 5 below. Referring to Figure 2, a schematic view of the jug 14 with the container 16 is shown. The jug 14 further includes a lid 38. The lid 38 extends over a rim 39 of the container 16. In the specific embodiment shown, the lid 38 is removable from the container 16. In other embodiments not shown, the lid 38 may be connected to the container 16, such as pivotally connected to the container 16. The lid 38 has an open state and a closed state. In the open state, the lid 38 at least partially uncovers a top opening of the food cavity such as for filling and/or emptying the container 16. In the closed state, the lid 38 completely covers the top opening of the food cavity such that filing and/or emptying of the container 16 is not possible. The open state of the lid 38 may be a position in which the lid 38 is completely removed from the container 16 such as in the case of a removable lid 38. Alternatively, in the case of a pivotable lid, the open state of the lid may be a position in which the lid 38 is at least partly rotated from the closed state into a state which is not the closed state. Referring to Figure 3, another schematic view of the machine 10 is shown. In Figure 3, the jugs 14 are arranged in the base 12 and the lids 38 are placed on the container. In other words, in Figure 3, the lids 38 of the jugs 14 are in the closed state. In such a position the machine 10 may be operated to process the liquid food substance inside the jugs 14. The closed state may be detected by the lid detection system explained in more detail in connection with Figures 4 and 5. Referring to Figure 4, a top view of the machine 10 is shown. For clarity, a cover plate of the machine 10 is removed. Figure 4 shows the MMI-sections 34 mentioned in connection with Figure 1. The MMI-sections 34 are part of a control unit 40. The control unit 40 is configured for controlling the machine 10 such as for activating or deactivating a motor of the machine, for example via the one or more MMI-sections 34. The control unit 40 includes a PCB 42. The PCB 42 may also be called a “substrate”. The PCB 42 is used for mounting electrical or electronic components 44. Examples of such components 44 are the MMI-sections 34. Further examples of such components 44 are integrated circuits, processors, capacitors or other electrical or electronic components. The components 44 may be mechanically and preferably electronically connected to the PCB 42. Figure 4 further shows the lid detection system 36. The lid detection system 36 and the control unit 40 are arranged inside the base 12. For example, the lid detection system 36 and the control unit 40 are arranged on a cover plate (not shown) of the base 12. As can be seen, the lid detection system 36 is mounted on the PCB 42. The lid detection system 36 may be at least partially rigidly mounted on the PCB 42. The lid detection system 36 may be mechanically and electronically connected to the PCB 42 and may be operatively connected to one or more of the components 44 of the control unit 40. Mounting the lid detection system 36 on the PCB 42 may save cables for wiring, may reduce the number of parts used for manufacturing the machine 10 and may reduce the size of the machine 10. The lid detection system 36 includes a sensor 46. The sensor 46 is used for sensing the open or closed state of the lid. The sensor 46 is at least partially mounted on the PCB 42, preferably rigidly mounted on the PCB 42. In the specific embodiment shown, the lid detection system 36 includes two sensors 46. The two sensors 46 are arranged in a side-by-side arrangement, similar to the side-by-side arrangement of the jugs 14. Each sensor 46 may be configured for sensing the closed or open state of a respective lid for each jug 14 individually. A mounting bracket 48 may be used to mount the two sensors 46. In other embodiments not shown, no mounting bracket 48 may be used. In the example of Figure 4, the sensors 46 are optical sensors with a line-of-sight or optical axis 50 as indicated by the dashed lines. In other examples not shown, the sensors 46 may be another type of sensor, for example a mechanical sensor. The optical sensors 46 are configured for sensing the closed or open state of the lid by measuring a light intensity or by using an optical beam. In the specific embodiment shown, the optical axes 50 of the optical sensors 46 confine an interior or internal angle 52. The interior angle 52 may be in a range between about 20° and about 170°. As shown, the sensors 46 may face away from one another other, i.e. their line of sight may go in opposite direction. The optical sensor 46 may include a light-sensitive diode, for example a photodiode, which senses a light intensity, for example along the optical axis 50. The optical sensor 46 may be arranged such that in the closed state of the lid, the sensor is at least partially covered by the lid, such that the light intensity received by the sensor 46 is at least partially reduced. The optical sensor 46 may detect the reduction and may determine the closed state of the lid when the received light intensity is below a predetermined threshold value. In another example, the optical sensor 46 may include a light emitter, such as a light emitting diode. The light emitter may transmit a beam towards the lid. The transmitted beam may be reflected by the lid and the reflected beam may be received by a light-sensitive diode, such as the photodiode. The optical sensor 46 may determine a runtime difference between the transmitted beam and the reflected beam and may determine the closed state of the lid if the runtime difference is below a predetermined threshold value. The optical sensor 46 may be connected to one or more components 44 of the control unit 40 and the one or more components 44 may be configured for analyzing a signal received from the optical sensor 36. The control unit 40 may be configured for comparing the received signal with expected values for the closed and/or open state of the lid and may optionally be configured for transmitting a notification to a user of the machine indicating the closed and/or open state of the lid. The control unit 40 may stop, interrupt or deactivate a motor of the machine 10 in case the lid detection system 36 or a sensor 46 thereof determines that the lid is in the open state. Referring to Figure 5, a detailed view of the machine 10 is shown. Figure 5 shows schematic view of the sensor 46 of the lid detection system 36. In the specific embodiment shown, the sensor 46 is an optical sensor with a line-of-sight or optical axis 50 indicated by the dashed line. Figure 5 shows the peripheral wall 30 that forms the seat for removably receiving the container 16. As can be seen in Figure 5, the peripheral wall 30 includes a cut-out or opening 54 at an upper end of the peripheral wall 30. The sensor 46 is arranged along the peripheral wall 30 and optionally above the container 16 such that the sensor 46 can receive light emitted through the cut-out 54. The sensor 46 may not extend or protrude into the cut-out 54. In other words, the sensor 56 may be arranged at a retracted position with respect to the cut-out 54. In the closed state of the lid, a wall of the lid, such as a side wall of the lid, may at least partially overlap with the cut-out 54 of the peripheral wall 30. A light intensity received by the sensor 46 and/or a runtime difference between a transmitted beam and a reflected beam may change and the change may be detected to determine the closed state of the lid. While not shown in Figure 5, the cut-out may be covered with a window made from a material transparent or translucent (e.g., when a light intensity is to be determined. Alternatively or additionally, the window may be transparent to the wavelength emitted and/or received by the sensor. A cut-out may not be necessary, e.g., where the peripheral wall of the seat is made from a material that is sufficiently transparent or translucent at the wavelength at which the sensor operates. Referring to Figure 6, another machine 56 for processing a liquid food substance such as milk or a milk-based substance is shown. As compared to the machine 10 explained in connection with Figures 1-5, the machine 56 of Figure 7 includes only a single jug 14 and the base 12 has, e.g, a substantially circular shape. The design and/or functionality of the machine 56 may, however, be similar to the machine 10 of Figures 1-5 so that, for example, the machine 56 may include a lid detection system as explained in connection with Figures 1-5.

Claims

1. A machine (10, 56) for processing a liquid food substance, such as milk or a milk-based substance, comprising: _{- a jug (14) having a container (16), the container (16)} delimiting a food cavity for containing said liquid food substance, and a lid (38) such as a removable lid (38) for covering the food cavity; _{- a base (12) having one or more walls forming a seat for} removably receiving the container (16); _{- a lid detection system (36) configured for detecting a closed} and/or an open state of the lid (38) when the container (16) is received in the seat; and _{- a control unit (40) for controlling the machine (10, 56), the} control unit (40) including a printed circuit board (42), characterized in that the lid detection system (36) includes a sensor (46) that is rigidly fixed to the printed circuit board (42). _{2. The machine of claim 1, wherein the control unit is} configured to compare: _{- a characteristic measured by the detection system indicative} of the closed state and/or the open state of the lid (38); to _{- an expected value thereof when the lid (38) is in the closed} state or in the open state. _{3. The machine of claim 1 or 2, wherein the control unit being} configured to indicate the closed state or the open state of the lid (38) to a user of the machine (10, 56). _{4. The machine (10, 56) of any preceding claim, wherein the} sensor (46) is at least one selected from the group including a mechanical sensor e.g. an electrically-monitored mechanical sensor, a magnetic sensor, a capacitive sensor, a conductive sensor, an inductive sensor, an optical sensor, a sonic sensor, such as an ultrasonic sensor, or a radar sensor. _{5. The machine (10, 56) of claim 4, wherein the sensor (46) is} an optical sensor configured for sensing the closed state and/or the open state of the lid (38) by measuring a light intensity or by using an optical beam. _{6. The machine (10, 56) of claim 5, wherein the sensor (46) is} configured for a retroreflective-beam arrangement and the closed state of the lid (38) is detected by transmitting a beam towards the lid (38) or a wall thereof and receiving an inverted beam reflected by the lid (38) or a wall thereof. _{7. The machine (10, 56) of any one of claims 1 to 6, wherein} the lid detection system (36) and the control unit (40) are arranged inside the base (12), such as connected to a cover plate of the base (12). _{8. The machine (10, 56) of any one of claims 1 to 7, wherein} the base (12) includes a peripheral wall (30) that delimits the seat for removably receiving the container (16), wherein the lid detection system (36) and in particular a sensor (46) thereof is arranged: _{- along the peripheral wall (30); and/or} _{- above the container (16) when the container (16) is received} in the seat in an operating position for processing the liquid food substance. _{9. The machine (10, 56) of claim 8, wherein the peripheral} wall (30) includes a cut-out (54) and the lid detection system (36), preferably the sensor (46), detects the closed state and/or the open state of the lid (38) through the cut-out (54). _{10. The machine (10, 56) of claim 9, wherein the lid detection} system (36), preferably the sensor (46), is arranged at a retracted position with respect to the cut-out (54), preferably such that the lid detection system (36) and preferably the sensor (46) does not extend into and/or through the cut-out (54). _{11. The machine (10, 56) of any one of claims 1 to 10, wherein} the control unit (40) is configured for: _{- receiving a signal provided by the lid detection system (36),} the signal being indicative of the closed state and/or the open state of the lid (38); _{- comparing the received signal with expected values for the} closed state and/or the open state of the lid (38), respectively; and optionally _{- transmitting a notification to a user of the machine (10, 56)} indicating the closed state or the open state of the lid (38). _{12. The machine (10, 56) of claim 11, wherein the sensor is a} or said optical sensor and the signal is indicative of: _{- a light intensity measured when the lid (38) is closed and/or} a light intensity measured when the lid (38) is open; or _{- a runtime difference between a transmitted beam directed to} the lid (38) and a received beam reflected from the lid (38). _{13. The machine (10, 56) of claim 12, wherein} _{- the container (16) includes a rim (39) delimiting a top} opening of the food cavity, _{- the lid (38) is arranged on the container (16) for closing} the top opening, _{- the lid (38) includes a side wall and} _{- the side wall is arranged in front of the sensor (46) when} the lid (38) is in the closed state. _{14. The machine (10, 56) of any one of claims 1 to 13, wherein} the base (12) is configured for receiving multiple jugs (14), such as in a side-by-side configuration, each jug (14) having a container (16) and a lid (38), such as a removable lid (38), and each container (16) being received in a corresponding seat of the base (12), wherein the lid detection system (36) is configured for detecting the open state and/or the closed state of the respective lid (38) individually for each jug (14). _{15. The machine (10, 56) of claim 14, wherein the lid detection} system (36) includes multiple sensors (46), e.g. multiple sensors rigidly fixed to the printed circuit board (42), and wherein each sensor (46) is configured for sensing the open state and/or the closed state of a respective lid (38), preferably wherein _{- the sensors (46) are arranged in a side-by-side configuration,} and/or _{- a line-of-sight axis (50) of a first sensor (46) and a line-} of-sight axis (50) of a second sensor (46) confine an internal angle (52) therebetween, the internal angle (52) being in a range between about 20° and about 170°.